var SEPARATION = 50, AMOUNTX = 50, AMOUNTY = 54;

var container;
var camera, scene, renderer;

var particles, particle, count = 0;

var mouseX =0, mouseY = -200;

var windowHalfX = window.innerWidth / 2;
var windowHalfY = window.innerHeight /2;

init();
animate();

function init() {

    container = document.createElement( 'div' );
    document.getElementById('three').appendChild( container );

    camera = new THREE.PerspectiveCamera( 80, window.innerWidth / window.innerHeight, 1, 10000 );
    camera.position.z = 1000;
    camera.position.y = 200;

    scene = new THREE.Scene();

    particles = new Array();

    var PI2 = Math.PI * 2;
    var material = new THREE.ParticleCanvasMaterial( {

        color: 0xffffff,
        program: function ( context ) {

            context.beginPath();
            context.arc( 0, 0, 1, 0, PI2, true );
            context.fill();

        }

    } );

    var i = 0;

    for ( var ix = 0; ix < AMOUNTX; ix ++ ) {

        for ( var iy = 0; iy < AMOUNTY; iy ++ ) {

            particle = particles[ i ++ ] = new THREE.Particle( material );
            particle.position.x = ix * SEPARATION - ( ( AMOUNTX * SEPARATION ) / 2 );
            particle.position.z = iy * SEPARATION - ( ( AMOUNTY * SEPARATION ) / 2 );
            scene.add( particle );

        }

    }

    renderer = new THREE.CanvasRenderer();
    renderer.setSize( window.innerWidth*0.57, window.innerHeight/3);
    container.appendChild( renderer.domElement );

    window.addEventListener( 'resize', onWindowResize, false );

}

function onWindowResize() {

    windowHalfX = window.innerWidth / 2;
    windowHalfY = window.innerHeight / 2;

    camera.aspect = window.innerWidth / window.innerHeight;
    camera.updateProjectionMatrix();

    renderer.setSize( window.innerWidth*0.57, window.innerHeight/3 );

}


function animate() {

    requestAnimationFrame( animate );

    render();


}

function render() {

    camera.position.x += ( mouseX - camera.position.x ) * .05;
    camera.position.y += ( - mouseY - camera.position.y ) * .05;
    camera.lookAt( scene.position );

    var i = 0;

    for ( var ix = 0; ix < AMOUNTX; ix ++ ) {

        for ( var iy = 0; iy < AMOUNTY; iy ++ ) {

            particle = particles[ i++ ];
            particle.position.y = ( Math.sin( ( ix + count ) * 0.3 ) * 50 ) + ( Math.sin( ( iy + count ) * 0.5 ) * 50 );
            particle.scale.x = particle.scale.y = ( Math.sin( ( ix + count ) * 0.3 ) + 1 ) * 2 + ( Math.sin( ( iy + count ) * 0.5 ) + 1 ) * 2;

        }

    }

    renderer.render( scene, camera );

    count += 0.1;

}
